Research Article

[Retracted] Study on Dynamic Evolution of Overburden Rock Movement and Mining-Induced Stress of Ultra-high Working Face

Table 1

Physical and mechanical parameters of coal and rock.

NameElastic Modulus (GPa)Poisson’s ratioTensile strength (MPa)Compressive strength (MPa)

Main roof30.9430.277.1425.55
Immediate roof40.3130.236.2814.25
Coal23.8720.252.111.68
Floor47.3500.226.7722.05